LANSING, Mich. (AP) — The Michigan Supreme Court on Wednesday said Michigan's Jan. 15 presidential primary can go forward, prompting New Hampshire to announce it will hold its primary on Jan. 8.

New Hampshire Secretary of State Bill Gardner set the date just hours after the court ruling, ending months of speculation, including the possibility that New Hampshire might push its primary into December in order to keep its spot first in the line.

The Michigan court's decision clears the way for the Republican and Democratic parties to take part in the Jan. 15 primary. Both already have filed letters with the secretary of state saying that's their plan, making Michigan the earliest state to vote after the Jan. 3 Iowa caucuses, Jan. 5 Wyoming GOP county conventions and the New Hampshire primary.

Democratic National Committee member Debbie Dingell of Michigan said she's confident the state party's executive committee will vote next week to approve the primary, allowing the party to file a new election plan with the DNC.

The party now has an election plan on file that sets up a Feb. 9 presidential caucus. It has kept open the possibility of holding a caucus even if the primary is held. Michigan Sen. Carl Levin had suggested holding the Michigan caucus the same day as the New Hampshire primary, but that now looks unlikely.

The Michigan Republican Party had filed a friend of the court brief supporting the primary, and state GOP Chairman Saul Anuzis welcomed the court ruling.

"This is good for Michigan, this is good for Republicans and it's good for the process," he said.

In its 4-3 decision Wednesday, the Michigan Supreme Court overturned lower court rulings that said the law setting up the primary was unconstitutional because it would let the state political parties keep track of voters' names and whether they took Democratic or GOP primary ballots but withhold that information from the public.

Justices Clifford Taylor, Maura Corrigan, Robert Young Jr. and Stephen Markman argued in the majority opinion that the political parties serve a public purpose by enlightening the public and encouraging an informed decision-making process, and that giving them sole access to the voter information does not violate the state constitution.

They sent the case back to Ingham County Circuit Court and ordered it dismissed.

Justices Michael Cavanagh, Marilyn Kelly and Elizabeth Weaver dissented, writing that the majority opinion risks causing the distinction between public and private purposes to lose all meaning and inviting "bad consequences for Michigan citizens in the future."

East Lansing political consultant Mark Grebner, one of several people who brought the suit, said he didn't plan to take any additional action at this point.

But Bill McMaster of Taxpayers United Michigan Foundation said he may file suit next week challenging the law because it doesn't protect voters' right to cast a secret ballot. Although each voter's actual vote will be secret, the political parties will have records showing which ballot — Democratic or Republican — each voter chose.

McMaster said the process will disenfranchise voters who don't want a record kept because they won't go to the polls. Primary supporters, however, say it will open the process to far more people than if the parties picked their favorites at caucuses and party conventions.

The court's decision will allow elections officials to restart election preparations that were put on hold when the circuit court ruled the primary law unconstitutional.

The state elections director and county clerks had warned they wouldn't have enough time to get ballots out to absentee voters if the court didn't issue a decision by noon Wednesday, but Secretary of State Terri Lynn Land said she's confident elections officials can prepare in time.

Anuzis, Dingell and Levin would like the state House to pass a bill next week restoring the names of four Democratic presidential candidates who've withdrawn from the ballot. Barack Obama, John Edwards, Joe Biden and Bill Richardson pulled their names from Michigan's primary ballot because the state violated DNC rules by moving up the election.

A Senate-passed bill would require all candidates' names to be on the ballot, although it also would give them the chance to withdraw again.

None of the Democratic candidates is campaigning in Michigan because the state broke DNC rules by moving its election ahead of Feb. 5. Dingell said restoring all eight names would force Democrats to fight over Michigan even if they can't campaign here because it wouldn't be just a contest between Hillary Rodham Clinton and some lesser-known candidates.

"With all the candidates on the ballot, this could be a make or break state for Republicans, and we'd like to make it that way for Democrats," Dingell said.

By holding its primary so early — in violation of the national Republican and Democratic parties' rules — Michigan stands to lose half of its delegates to the Republican National Convention, reducing the number to 30, and all of its 156 delegates to the Democratic National Convention.

Michigan officials in both parties say it's likely the presidential nominees would seat the delegates anyway. Democrats may seek a waiver to the DNC rules.